Do Antioxidant Supplements and Exercise Mix?

The antioxidant resveratrol – the one found in red grapes, and therefore, red wine – countered the effects of aerobic exercise in older men, according to a new study in theJournal of Physiology.

Before you skip the merlot, read on: the research does not mean older men, or anyone, should avoid foods with resveratrol or other antioxidants. Rather, the study suggests that “more,” particularly in the case of supplements, is not necessarily better, or for that matter, good.

Researchers at the University of Copenhagen had 27 inactive men with an average age of 65 perform high-intensity exercise for eight weeks. During the study, half the men took supplements containing 250 milligrams of resveratrol, and the rest took a placebo.

Not surprisingly, after exercising for two months, the men were fitter and healthier. Their blood pressure and cholesterol levels were lower, and they improved their VO2max (an aerobic fitness benchmark). But those beneficial effects, and others, were greatly diminished in the subjects taking resveratrol.

The study, said Lasse Gliemann, a Ph.D. candidate who worked on the experiment, is a reminder that antioxidant supplementation is not fully understood.

“We gave a dose of 250 mg/day of trans-resveratrol in a slow release pill. A bottle of red wine has roughly 2 to 12 mg resveratrol. Therefore, our results cannot be extrapolated to any antioxidant that you would get from a healthy diet rich in veggies and fruits (and red wine),” Gliemann told Runner’s World.

Resveratrol and other antioxidants tame the free radicals produced during exercise. Because age is associated with greater levels of free radical production (which are harmful to cells), the researchers hypothesised that a resveratrol boost would help the body cope with the increased free radical presence. It had the opposite effect.

“These findings suggest that if you are aged, supplementing with resveratrol is not a wise move if you are to get the most out of your training (at least in the dose we tested),” said Gliemann.

This isn’t the first time research has found that antioxidants may interfere with the benefits of exercise, as science journalist Alex Hutchinson points out. Hutchinson explains that free radicals signal the body to adapt to the stress of exercise. If you interfere with that signal with whopping doses of antioxidants, exercise’s benefits are blunted.

“This is all about the high-dose supplement,” said Gliemann. “It does not interfere with eating a healthy diet.”


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